1. Field of the invention
The present invention relates to a keyboard instrument and a fallboard structure thereof, and more particular, to a fallboard structure including a fallboard that covers a keyboard section, and a keyboard instrument having an optical display section for performance assist or the like.
2. Description of the Related Art
Conventionally, piano-based electronic keyboard instruments have been known that include an ingenious fallboard structure, as disclosed in Japanese Utility Model Publication (Kokoku) No. H07-49511 and Japanese Patent Laid-open Publication (Kokai) No. 2004-302419 (hereinafter referred to as first and second prior arts, respectively). In some piano-based electronic keyboard instruments, much efforts have been made to provide an acoustic piano-like appearance and performance feeling. Such efforts have been made to improve a fallboard structure as well as various parts such as tone generator system, keyboard mechanism, and exterior mechanism.
The acoustic piano has a long history and a general concept thereof is fixed such as, for example, as follows: Piano actions are disposed rearward and upward of keys. A front plate is disposed rearward and upward of a keyboard section, and the piano actions and the like in an instrument body are hidden by the front plate. Further, a fallboard provided solely to cover the keyboard section is adapted to be raised and superimposed on the front plate in a facing relation therewith when it is open.
A piano-based electronic keyboard instrument of a type not provided with the just mentioned external and structural features that are proper to the acoustic piano is no longer recognized as belonging to the acoustic piano.
For example, the keyboard instrument according to the first prior art is designed that the fallboard covering the keyboard section can be opened and closed by being slid in a front-to-rear direction. However, the fallboard motion and the external appearance of the fallboard after being opened quite differ from those of the acoustic piano. In the keyboard instrument according to the second prior art, an operation panel is provided on a rear surface of the fallboard. At the time of operation for performance, the fallboard is made open and the operation panel is exposed for operation. This keyboard instrument differs in external appearance from the acoustic piano.
By the way, it is expected that musical tones can be effectively sounded by making a tone generator section such as a sound board and strings disposed rearward of the keyboard open not only toward upward but also toward the player.
In addition to the first prior art, there is known a keyboard instrument having a fallboard structure in which the fallboard covering the keyboard section is housed in the instrument body when the fallboard is open, as disclosed in Japanese Patent Publication (Kokai) No. H11-65552 (hereinafter referred to as the third prior art).
For example, in the fallboard structure according to the first prior art, the fallboard is slidingly moved rearward and housed in the instrument body. In the fallboard structure according to the third prior art, the fallboard is adapted to be folded on the front plate such that the front plate is moved rearward with the progress of opening the fallboard.
With the fallboard structures according to the first and third prior arts, however, the fallboard at the time of being opened interferes with a space rearward and upward of the keyboard section. Thus, the space rearward and upward of the keyboard section must always be left unoccupied, making it impossible to dispose functional element parts of the keyboard instrument in that space, which is disadvantageous from the viewpoint of space-saving.
Further, there is known a keyboard instrument having optical displays for optical performance assist or the like that are provided so as to correspond to respective ones of the keys, as disclosed in Japanese Laid-open Patent Publication No. 2000-181455 (hereinafter referred to as the fourth prior art). In the fourth prior art, optical bodies, as optical displays, made of a transparent resin are each disposed on a rear end of an exposed upper surface portion of a corresponding one of the keys, for example. Light emitted from a light-emitting body is diffused by a corresponding optical body and then emitted from a front surface and an upper slanted surface of the optical body, to be recognized by the player.
With the fourth prior art, however, the optical bodies exposed at the time of musical performance are always visible from the player and only recognized as emitting light. As a result, the presence of the optical bodies are always conscious and the entire instrument is recognized as an electronic musical instrument.
Thus, even when this keyboard instrument is fabricated such that the instrument body has its external appearance as close as possible to that of the acoustic piano, there still remains the concept of an electronic instrument at least at the time of musical performance, making it difficult to realize a musical performance with an acoustic piano-like appearance.
Furthermore, an electronic keyboard instrument must have a panel section in which electronic instrument's functional elements such as operators are disposed. Thus, the electronic keyboard cannot be recognized as being similar to the acoustic piano, if there is no element corresponding to the front plate on the rear side of the keyboard section. For example, when a panel section is disposed at a location where the front plate is usually disposed, the panel section is always visible from the player, which puts the electronic instrument away from having an acoustic piano-like appearance.
Nevertheless, when utilized for performance assist or the like, the optical displays must be visible without difficulties. Further, the electronic keyboard instrument must have user-friendliness for operation of the panel section.